1. Field of the Invention
This invention relates to buckets of the type used on excavators, loaders, draglines, and the like, and, more particularly, to buckets having novel wear-resistant strips.
2. Description of the Prior Art
In the earthmoving field and, in particular, that portion of the field devoted to the use of buckets, the highly abrasive nature of the material being worked upon wears away the bottom wrapper strip and side plates of the bucket and, in particular, the corners of said bucket. One method of combating the wear on the corners and bottom of the bucket is to provide hardened wear strips or overlays having a hard facing. To increase the life of the strips, it has been proposed to increase the thickness of the plates or to increase the hard facing, but both of those solutions are undesirable since it increases the weight of the bucket which increases the stresses on the operating parts of the equipment.
One other solution was to form the excavating implement with grooves or sockets formed in the surface thereof. The grooves or sockets were then filled with a wear-resistant alloy, usually by the alloy being produced in the form of a rod, which alloy then was deposited by electric or oxy-acetylene welding directly into the grooves or sockets of the implement. In some cases, in addition to filling the socket or the grooves, the whole surface of the implement was coated with a coating of the material of the rod. The principal problem with this attempted solution was that the base material surrounding the grooves or sockets would errode away along with the wear-resistant material.
A second attempted solution was to embed particles of hard material in the surface of the implement. This could be done by depositing the hard particles in the base of the mold or positioning the particles in the base of the mold attached to a support strip. The base material of the casing is then poured in to set the hard particles in place. The principal problem with this solution was similar to that of the previous solution in that the material around the particles wore away with the particles so that once the depth of the particles was reached, there was no longer any substantial wear resistance.
In another solution, cylindrical inserts of a hard wear-resistance material are inserted directly into apertures in the face of an implement such that as the inserts wore away, the material surrounding the inserts, likewise, wore away.
Still another solution was to embed inserts of a material in the surfaces of pads on a tool such that as the inserts wore away, the surrounding materials also wore away.
In the four last-named solutions, the base material of the implement wore away with the inserts so that eventually the tool had to be replaced. Admittedly, the inserts prolonged the life of the tool or implement, but only temporarily.